TWI497328B - Consider the reconstruction method and device of the scan chain of the program group - Google Patents

Description

Reconstruction method and device for considering scan chain of plan group

The invention relates to a method and a device for reconstructing a scan chain, in particular to a method and a device for reconstructing a scan chain in a planning and design stage of a wafer module.

When module planning is performed on a wafer containing a test chain, the arbitrariness of the distribution of the scanning elements will result in excessive wiring between the various planning groups. At the same time, each planning group also needs to create more 埠 to undertake the input and output of the scanning signal. This makes the demand for resources of each plan group in the top-level application, which increases the difficulty of design. In order to reduce the number of lines on the plan group and the number of lines between the groups caused by the scan chain passing through the plan group, it is necessary to reconstruct the scan chain, that is, adjust the position of the scan elements to form a new scan chain.

1 is a method for reconstructing a scan chain: first, in step 70, the start point of the scan chain is used as a reference component, and in step 71, the distance of the reference component to all other available scan components in the scan chain is calculated. Wherein a scanning element is closest thereto; the reference element is coupled to the nearest scanning element at step 72; the scanning element closest to it is used as a reference element at step 73; and then at step 74 it is checked whether the reference element is The last available scanning element; if so, it is connected to the end of the scan chain at step 75; otherwise, returns to step 71.

The reconstruction method of the scan chain only considers the distance relationship between the scanning elements, and does not consider the position information of the planning group where each scanning element is located, so the obtained scanning chain may be shortened by the length and may be more than before the reconstruction. The program group resulted in too many connections between the program groups. Even after reordering, the connection between the sputum and the planning group on the program group is reduced, but in fact, there is still room for further reduction of snagging and wiring through the reconstruction of the scan chain.

In view of this, the industry still needs a reconstruction technology solution of the scan chain to solve the problem of excessive connection between the group and the group.

The present invention provides a structure reconstruction method and apparatus for considering a scan chain of a plan group, which shortens the length of the scan chain and allows each scan chain after reconstruction to pass through as few plan groups as possible, thereby making The total number of connections between the group and the group on the drawing group is minimized.

The present invention proposes a scan chain reconstruction method, which includes a first stage reconstruction, the first stage reconstruction comprising: stepping a pair of scan chains for classification, wherein the start and end points are scanned in a same plan group The chain is classified into the first scan chain set; the scan chain whose start point and end point are not in the same plan group is classified as the second scan chain set; the start and end points are all classified into the third scan chain set in a top scan chain; Reconstructing the scan chain in the first scan chain set until the first scan chain set is empty; step 3 reconstructing the scan chain in the second scan chain set until the second scan chain set is empty; and step 4 reconstructing The scan chain within the third scan chain set until the third scan chain set is empty.

According to an embodiment, the step 2 further comprises: extracting, from the first scan chain set, a scan chain that requires the least number of scan components; and checking whether the number of available scan components in a plan group of the end of the scan chain is Satisfying the scan chain needs; if sufficient, the scan elements available in the plan group are assigned to the scan chain according to the required number of scan chains; otherwise, all available scan elements in the plan group are assigned to the scan chain, and The scan chain is placed in a third scan chain set. The step 3 further includes: extracting the scan component from the second scan chain set to require a minimum number of scan chains; determining whether the scan chain has an endpoint at the top layer: if yes, determining the plan of the other end of the scan chain Whether the number of available scanning elements in the group meets the needs of the scan chain; if the number of scanning elements in the planning group is sufficient, the scanning elements in the planning group are allocated to the scanning chain according to the required quantity; otherwise, the counting A scan element within the draw group is assigned to the scan chain and the scan chain is added to the third scan chain set. Otherwise, for the two plan groups in which the two ends of the scan chain are located, calculate the total number of scan component requirements of all scan chains from which the scan elements may be selected; and determine whether the available scan elements in the two plan groups are Satisfying the needs of the scan chain. If satisfied, the scan component is preferentially assigned to the scan chain from a plan group having a smaller total number of scan component requirements, and the insufficient amount is selected from another plan group; otherwise, two The available scan elements in the plan group are assigned to the scan chain and the scan chain is placed in the third scan chain set. The step 4 further includes: extracting a scan chain of the scan element from the third scan chain set; checking whether a plan group contains more scan components than the scan chain requiring the most scan chain. : If yes, the scan chain is selected from a plan group having the fewest number of scan components; otherwise, the scan component is assigned to the scan chain from the plan group having the largest number of available scan components, and finally to the top selection . The scan chain reconstruction method can further include a second stage reconstruction in which the scan elements required to reconstruct the scan chain within the same plan group are redistributed based on the scan element position, wherein adjacent Scanning elements that are close to a scan chain will be assigned to the scan chain.

The present invention also provides a scan chain reconstruction apparatus corresponding to the scan chain reconstruction method, which includes a first level reconstructor and a second level reconstructor. The first level reconstructor comprises: a classifier for classifying a plurality of scan chains, wherein the scan chain within the same plan group of the start point and the end point is classified into the first scan chain set; the start point and the end point are not in the same plan group The scan chain within is classified as a second scan chain set; the start and end points are all classified into a third scan chain set in a top scan chain; an allocator is communicatively coupled to the classifier; it first reconstructs the first scan Scanning chain within the chain set until the first scan chain set is empty; then reconstructing the scan chain in the second scan chain set until the second scan chain set is empty; finally reconstructing the third scan chain set The scan chain is scanned until the third scan chain set is empty.

The scan chain reconstruction method and device of the present invention not only considers the position information of the scan chain and the scanning component, but also calculates the position information of the start and end points of the scan chain in the plan group or the top layer, thereby minimizing the position on the plan group. The number of connections and the number of connections between groups to obtain better planning and design results; reduce the need for upper resources and the difficulty of subsequent design.

The technical features of the present invention have been briefly described above, and the detailed description below will be better understood. Other technical features constituting the subject matter of the patent application of the present invention will be described below. It is to be understood by those of ordinary skill in the art that the present invention may be practiced otherwise. It is to be understood by those of ordinary skill in the art that this invention is not limited to the scope of the invention.

To better understand the spirit of the present invention, the following further describes the preferred embodiments of the present invention.

The invention provides a method and a device for reconstructing a scan chain based on a planning group in a planning and design stage of a wafer module.

According to an embodiment of the invention, the scan chain reconstruction method based on the plan group comprises two stages. First, in the first stage of scan chain reconstruction, with the number of scan elements in the plan group as the main basis, a scan chain is selected from as few plan groups as possible. In the process of reconstruction, the relationship between the start and end points of the scan chain and the plan group is fully considered, so that the scan components in the same plan group are preferentially assigned to the scan chain associated with it, thereby reducing the possibility between the plan groups. The number of connections that appear. Then, in the second stage of the scan chain reconstruction, based on the position information of the scanning component as the main basis, the scanning component is allocated in one planning group, and the adjacent scanning components are allocated to the same scanning chain, thereby reducing each scanning. The length of the wiring between the scanning elements within the chain.

The following is a detailed description of the first and second phases of the scan chain reconstruction:

The first stage of reconstruction: In the first stage of scan chain reconstruction, the order of reconstruction is based on the position of the start and end points of each scan chain, so that the scan chain does not wear the plan group in which it is located. Wherein, the scan chain in the same plan group as the start point and the end point is classified as the first scan chain set, and the scan elements are preferentially selected from the plan group in which they are located; the scan chains in which the start point and the end point are not in the same plan group are classified as The second scan chain set is processed in a lower priority order; the scan chain at the top and end points is classified as the third scan chain set and is finally processed.

Specifically, as shown in FIG. 2, it is first determined in step 10 whether the first scan chain set is empty. If there is a scan chain in which the start point and the end point are in the same plan group, then the process proceeds to step 11 where the reconstructed start point and the end point are the same. The scan chain within the plan group. Otherwise, in step 12, it is determined whether the second scan chain set is empty. If there is a scan chain in which the start point and the end point are not in the same plan group, or only one end point, that is, the start point or the end point is at the top scan chain, the process proceeds to step 13 Constructing a scan chain within the second scan chain set. Otherwise, proceed to step 14 to determine whether the third scan chain set is empty. If it is not empty, the scan chain in the third scan chain set is reconstructed in step 15; if empty, the process proceeds to step 16 to end the first stage reconstruction.

As shown in FIG. 3, in step 11, starting from step 110, the scan chain of the first scan chain set that requires the least number of scan components is found and taken out from the first scan chain set. In step 111, it is checked whether the number of available scanning elements in the plan group in which the start and end points of the scan chain are located satisfies the scan chain requirement. If sufficient, in step 112, the scan elements available in the plan group are assigned to the scan chain; otherwise, proceed to step 113 to assign all of the available scan elements in the plan group to the scan chain and place them in the first The three scan chain sets are used to continue selecting the scanning elements in step 14.

As shown in FIG. 4, when the scan chain in the second scan chain set is reconstructed, in order to scan the chain as little as possible, the scan group needs to be drilled out, and in step 130, the scan component needs in the second scan chain set are also found. The smallest number of scan chains are taken from the second scan chain set. At step 131, it is determined whether the scan chain has an endpoint (start or end point) at the top level. If so, proceed to step 132 to determine if the number of scanning elements within the planning group in which the other endpoint (end point or starting point) is located meets the scan chain requirements. If the number of scanning elements in the planning group is sufficient, the process proceeds to step 133 where the scanning elements in the planning group are allocated to the scanning chain according to the required number. Otherwise, proceeding to step 134, the scan elements within the plan group are assigned to the scan chain and the scan chain is added to the third scan chain set. Otherwise, the start and end points of the scan chain are in two different plan groups, then step 135 is entered, for which the total number of scan chains for all scan chains from which the scan elements may be selected is calculated for each of the two plan groups. At step 136, it is determined if the available scanning elements within the two planning groups meet the needs of the scan chain. If yes, in step 137, the scan component is preferentially assigned to the scan chain from a plan group having a smaller total number of corresponding scan component requirements, and the insufficient amount is selected from another plan group; otherwise, the process proceeds to step 138 to The available scan elements in the plan group are assigned to the scan chain and the scan chain is placed in the third scan chain set.

As shown in FIG. 5, in step 15, the reconstruction start and end points are both in the scan chain of the top layer and the scan chain in which the reconstruction is not completed in the first two steps 10, 11. In step 150, the scan chain from the desired scan element is taken from the third scan chain set. In step 151, it is checked whether a plan group contains more scan elements than is required for the most demanding scan chain. If so, the scan chain is selected from the set of plans containing the fewest number of scan elements in step 152; otherwise, at step 153 the scan chain is selected from the set of plans containing the largest number of scan elements available, and finally to the top level selection. In this way, the plan group is prevented from being split by more scan chains, reducing the flaws on the plan group.

Second-stage reconstruction: Since the scan chain is a scanning component within the random selection plan group when reconstructing in the first stage of the scan chain, it is possible that the selected scanning element is far away from it and the component is close to it. Not selected. Thus, during the second phase of reconstruction, the scan elements required for the scan chain within the same plan group will be redistributed based on the scan element position. Among them, scanning elements adjacent to and close to a scan chain will be allocated to the scan chain, thereby shortening the total length of the wiring between the scan elements in the scan chain.

After the above two stages of reconstruction are completed, the scanning elements of each scan chain can also be reordered to minimize the total number of wirings of the scan chain.

As shown in FIG. 6, three scan chains 50, 51, 52 located within two plan groups 40, 41 and top layer 42 will be reconstructed in accordance with an embodiment of the present invention. The first plan group 40 includes seven scanning elements a, f, j, h, k, m, n; the second plan group contains four scanning elements b, c, i, l, and the top layer has three scans. Element d, e, g. The structural information of the three scan chains 50, 51, and 52 are respectively: the scan chain 50 includes three scan elements a, b, and c, and the start point 500 and the end point 501 are both in the first plan group 40; thus, in the two The plan group 40, 41 forms two intersecting lines, four turns; the scan chain 51 includes d, e, f, g, h, a total of five scanning elements, the starting point 510 in the second plan group 41, the end point 511 At the top layer 42; thus forming three intersecting lines, five turns between the two planning groups 40, 41; the scanning chain 52 comprises six scanning elements of i, j, k, l, m, n, the starting point 520 and the end point 521 are all on the top layer 42; thus forming five intersecting lines, eight turns, between the two plan groups 40,41.

If the three scan chains 50, 51, 52 are only reordered according to the existing method, taking the scan chain 50 as an example, in which all of the scan elements a are closest to the start point 500, then the start point of a and the scan chain 50 is first. 500 connections. Then, by calculating b, the closest to distance a in c is b, connecting a and b. Then connect b with c, c and end point 501. Thus, as shown in FIG. 7, the three scan chains 50, 51, 52 are adjusted such that the scan elements of the scan chain 50 are sorted as a, b, c, still two intersecting lines, four turns; scanning of the scan chain 51 The components are sorted into e, d, g, f, h, with two intersecting lines and three turns; the scanning elements of the scan chain 52 are sorted into j, m, n, k, l, i, with three intersecting lines, four port.

It can be seen that after simple sorting, the lines of the planning groups 40 and 41 and the interconnections between them are reduced, but in fact, there are still many defects and connections that can be reduced.

In the following, the three scan chains 50, 51, 52 are reconstructed in two steps according to the invention: firstly, according to the information of the three scan chains 50, 51, 52, that is, the scan components and the number of scan elements included in each scan chain, each scan component The three scan chains 50, 51, and 52 are classified by the plan group and the start and end positions of each scan chain. Wherein, the starting point 500 of the scan chain 50 is the same as the end point 501 in the plan group 40, and then the first scan chain set is placed; the start point 510 and the end point 511 of the scan chain 51 are located in the second plan group 41 and the top layer 42, respectively, It is placed in the second scan chain set; and the start point 520 and the end point 521 of the scan chain 52 are both located on the top layer 42, and are classified into the third scan chain set. The scanning elements within the random selection plan set 40 are assigned to scan chains 50 within the first scan chain set, such as a, f, h. Next, a scan element is assigned to the scan chain 51 within the second scan chain set. Since the end point 511 of the scan chain 51 is at the top layer 42, the elements b, c, i, l in the plan group 41 where the start point 510 is located are assigned to the scan chain 51. At this time, the scan chain 51 has not been filled yet, and thus is placed in the third scan chain set.

At this time, there are two scan chains 51, 52 in the third scan chain set that need to be constructed, wherein the scan chain 51 requires one scanning element, and the scan chain 52 requires six scanning elements, so the scanning element is first selected for the scan chain 52. Also, the plan group 40, which has the largest number of scan elements, has only four available scan elements, and thus the available scan elements j, k, m, n in the plan group 40 and d, e on the top layer are assigned to the scan chain 52. Finally, the remaining available scanning elements, i.e., the g of the top layer 42, are selected for the scan chain 51.

After this level of reconstruction, the composition of each of the scan chains 50, 51, 52 is as shown in Fig. 8. It can be seen that the number of connections between the frame and the plan group is minimized, as follows: Scanning elements of the scan chain 50 A, f, h, and the scan chain 50 does not leave the plan group 40; the scan elements of the scan chain 51 are b, c, i, l, g, with a cross line, a turn; scan elements of the scan chain 52 For j, k, m, n, d, e, there are two cross lines, two 埠.

Next, if the scan chain is subjected to the second level reconstruction, since the scan elements of the plan group 41 are all allocated to the scan chain 51, the second level reconstruction is performed on the plan group 40 and the top layer 42, respectively. The second level of reconstruction may employ any single group or top level optimization method, such as a ranking method that considers penalty parameters. In this embodiment, only the common distance sorting is taken as an example. In the plan group 40, m, n, k are assigned to the scan chain 50, and h, j, a, and f are assigned to the scan chain 51; 42, e is assigned to the scan chain 51, and d, g are assigned to the scan chain 52.

As shown in FIG. 9, the composition of the three scan chains becomes: scan chain 50 includes n, m, k, only within the plan group 40, and the length is shortened; the scan chain 51 includes b, i, c, l, e There is a cross line, a 埠, and the length is shortened; the scan chain 52 includes h, j, a, f, g, d, has two intersecting lines, two 埠, and the length is shortened.

Corresponding to the reconstruction method of the scan chain of the present invention, the present invention provides a reconstruction apparatus 2 for a scan chain. As shown in FIG. 10, the structure reconstruction apparatus of the scan chain of the present invention includes a first stage reconstructor 20 and a second stage reconstructor 21.

All scan chains are first input to the first stage reconstructor 20, and the first stage reconstructor 20 uses the number of scanning elements in the plan group as the main basis in the first stage of the scan chain reconstruction. The scan chain selects the scan elements from as few plan groups as possible. The first level reconstructor 20 will fully consider the relationship between the start and end points of the scan chain and the plan group during the reconstruction process, so that the scan elements in the same plan group will be preferentially assigned to the scan chain associated with it. , which is a good way to reduce the number of connections that may occur between the planning groups.

The scan chain is reconstructed by the first stage reconstructor 20 and input to the second stage reconstructor 21 therefrom. In the second stage of scan chain reconstruction, the second stage reconstructor 21 uses the position information of the scanning component as the main basis, performs scanning component allocation in one planning group, and assigns adjacent scanning components to the same scanning chain. Thereby reducing the length of the wiring between the scanning elements in each scan chain.

The first stage reconstructor 20 and the second level reconstructor 21 of the reconstruction apparatus 2 of the scan chain are described in detail below as follows:

The first stage reconstructor: the first stage reconstructor 20 needs to complete the first stage task of the scan chain reconstruction, and the order of reconstruction is based on the positions of the start and end points of each scan chain, so that the scan chain is not worn as much as possible. Out of the program group in which it is located. As shown in FIG. 11, the first level reconstructor 20 includes a classifier 200 that receives all scan chains from the input port 201 and classifies them. The scan chain in which the start point and the end point are in the same plan group is classified as the first scan chain set, and the scan elements are preferentially selected from the plan group in which they are located; the scan chains in which the start point and the end point are not in the same plan group are classified as the first The second scan chain set is processed in a lower priority order; the scan chain at the top and end points is classified as the third scan chain set and is finally processed.

A distributor 202 is communicatively coupled to the classifier 200, which first checks if the first scan chain set is empty, such as a scan chain having a start point and an end point within the same plan group, then reconstructing the start point and the end point in the same plan The scan chain within the group. Otherwise, it is checked whether the second scan chain set is empty. If there is a scan chain whose start point and end point are not in the same plan group, or only one end point, that is, the start or end point is at the top scan chain, the second scan chain is reconstructed. The scan chain within the collection. Otherwise check if the third scan chain set is empty. If not empty, the scan chain in the third scan chain set is reconstructed; if empty, the first stage reconstruction is ended.

Specifically, the distributor 202 first finds a scan chain in the first scan chain set that requires the least number of scan components, and takes it out from the first scan chain set. Check that the number of available scan elements in the plan group where the start and end of the scan chain are located meets the scan chain requirements. If sufficient, the scan elements available in the plan group are assigned to the scan chain by the required amount; otherwise, all of the available scan elements in the plan set are assigned to the scan chain and placed in the third scan chain set.

After the scan chain reconstruction of the first scan chain set is completed, the first stage reconstructor 20 reconstructs the scan chain within the second scan chain set. In order to scan the chain as little as possible out of the plan group, the distributor 202 also finds the scan chain that requires the least number of scan elements in the second scan chain set and extracts it from the second scan chain set. Determine if the scan chain has an endpoint (start or end) at the top. If so, it is determined whether the number of scanning elements in the planning group where the other endpoint (end point or starting point) is located satisfies the scanning chain requirement. If the number of scanning elements in the planning group is sufficient, the scanning elements in the planning group are allocated to the scanning chain according to the required number; otherwise, the scanning elements in the planning group are allocated to the scanning chain, and The scan chain is added to the third scan chain set. If the start and end points of the scan chain are in two different plan groups, for each of the two plan groups, the total number of scan chains required for the scan elements from which the scan elements may be selected is calculated. It is determined whether the available scanning elements within the two planning groups meet the needs of the scan chain. If yes, the scan component is preferentially assigned to the scan chain from a plan group corresponding to the total number of scan component requirements, and the insufficient amount is selected from another plan group; otherwise, the two plan groups are available. Scanning elements are assigned to the scan chain and the scan chain is placed in a third scan chain set.

Upon checking that the second scan chain set is empty, the first stage reconstructor 20 reconstructs the scan chain with the start and end points at the top level, and the scan chain that did not complete the reconstruction before completion. The splitter 202 is taken from the scan chain of the third scan chain of the classifier 200 from the scan chain of the most desired scan elements. Check if a plan group contains more scan elements than is needed for the most demanding scan chain. If so, the scan chain is selected from a set of plans containing the fewest number of scan elements; otherwise, the scan chain is selected from the set of plans containing the largest number of scan elements available, and finally to the top level selection. In this way, the plan group is prevented from being split by more scan chains, reducing the flaws on the plan group.

The second stage reconstructor: The first stage reconstructor 20 is transmitted from the output port 203 to the second stage reconstructor 21 after the end of the reconstruction. Since the first stage reconstructor 20 reconstructs the scan chain, the scan elements in the randomly selected plan group are allocated to the scan chain, and it is possible that the selected scan element is far from the scan chain and is close to it. The components are not selected. Thus the second stage reconstructor 21 will redistribute the scanning elements required for the scan chain within the same set of plans based on their position. Among them, scanning elements adjacent to and close to a scan chain will be allocated to the scan chain, thereby shortening the total length of the wiring between the scan elements in the scan chain.

Compared with the prior art, the method and apparatus for reconstructing a scan chain of the present invention only considers a technical solution for reducing the length of a scan chain. In the first stage of reconstruction, the global scan chain is classified according to the position of its end point, so that the scan chain is exhausted. There may be fewer plan groups. Therefore, the connection between the frame and the plan group on the plan group is greatly reduced, which reduces the resource requirement and the difficulty of subsequent design. The present invention can also perform the second stage reconstruction after the first stage, and the scanning elements required for the scan chain in the same plan group are redistributed based on their positions, thereby further shortening the length of the scan chain.

The technical contents and technical features of the present invention have been disclosed as above, and those skilled in the art can still make various substitutions and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention should be construed as not limited by the scope of the invention, and the invention is intended to

20. . . First level reconstructor

twenty one. . . Second level reconstructor

10~16. . . step

40, 41. . . Two planning groups

42. . . Top

50~52. . . Three scan chains

51. . . Scan chain

52. . . Scan chain

71~75. . . step

110~113. . . step

130~138. . . step

150~153. . . step

200. . . Classifier

201. . . Input 埠

202. . . Distributor

203. . . Output埠

500. . . starting point

501. . . end

510. . . starting point

511. . . end

520. . . starting point

521. . . end

Figure 1 is a flow chart for performing scan chain reconstruction using distance sorting;

2 is a flow chart of the first stage reconstruction of the present invention;

3 is a flow chart of reconstruction of a scan chain within a first scan chain set in a first stage reconstruction of the present invention;

4 is a flow chart of reconstruction of a scan chain within a second scan chain set in a first stage reconstruction of the present invention;

5 is a flow chart of reconstruction of a scan chain within a third scan chain set in a first stage reconstruction of the present invention;

6 is a schematic diagram of a scan chain when a wafer is not optimized after design;

7 is a schematic diagram of sorting the scan chain of FIG. 6 after optimization;

8 is a schematic diagram of the first stage reconstruction of the scan chain of FIG. 6;

9 is a schematic diagram of the second stage reconstruction of the scan chain of FIG. 6;

Figure 10 is a block diagram showing the structure of a reconstruction apparatus for a scan chain of the present invention;

Figure 11 is a block diagram showing the structure of the first stage reconstructor of the present invention.

10~16. . . step

Claims (16)

A method for reconstructing a scan chain, the method comprising: step 1: classifying the plurality of scan chains, wherein a scan chain start point and a scan chain end point are classified into a first scan chain set in a same plan group; The scan chain that is not in the same plan group as the scan chain start point and the scan chain end point is classified as the second scan chain set; the scan chain start point and the scan chain end point are both classified into the third scan chain set in the top scan chain; Step 2: For each scan chain in the first scan chain set, the scan chain is reconstructed by using scan elements in the same plan group corresponding to the scan chain until the first scan chain set is empty, wherein if the The scanned elements required for the reconstructed scan chain are not satisfied by the remaining scan elements in the corresponding plan group, and the remaining scan elements in the corresponding same plan group are given to the scan chain and the scan is performed Moving the chain to the third scan chain set; step 3: reconstructing the scan chain by using scan elements in different scan plan groups corresponding to the scan chain for each scan chain in the second scan chain set Until the second scan chain set is empty, wherein if the required scan elements of the reconstructed scan chain cannot be satisfied by the remaining scan elements in their corresponding different plan groups, the corresponding differences are The remaining scanning elements in the planning group are given to the scan chain and the scan chain is moved to the third scan chain set; step four: reconstructing each scan chain in the third scan chain set until the third The scan chain set is empty. According to the method for reconstructing a scan chain according to claim 1, the step 2 further includes: extracting, from the first scan chain set, a scan chain that requires the least number of scan components; and checking the end of the scan chain. Whether the number of available scanning elements in the drawing group meets the needs of the scanning chain; if sufficient, the available scanning elements in the planning group are assigned to the scanning chain according to the required number of the scanning chain; otherwise all the available in the planning group are available The scan element assigns the scan chain and places the scan chain into a third scan chain set. The method for reconstructing a scan chain according to claim 1, wherein the step 3 further comprises: removing a scan chain from the second scan chain set by a minimum number of scan chains; determining whether the scan chain has an endpoint The top layer; if so, in step I, it is determined whether the number of available scanning elements in the plan group of the other end of the scan chain satisfies the scan chain requirement; otherwise, in step II, the two ends of the scan chain are located A group of paintings that computes the total number of scanning component requirements for all scan chains from which scanning elements may be selected. The method for reconstructing a scan chain according to claim 3, wherein the step I further comprises: If the number of scanning elements in the planning group is sufficient, the scanning elements in the planning group are allocated to the scanning chain according to the required number; otherwise, the scanning elements in the planning group are allocated to the scanning chain, and the A scan chain is added to the third scan chain set. The method for reconstructing a scan chain according to claim 3, wherein the step II further comprises: determining whether the available scan elements in the two plan groups meet the needs of the scan chain, and if so, from the corresponding scan component requirements The scan component is preferentially assigned to the scan chain in a smaller total number of plan groups, and the insufficient scan components are selected from another plan group; otherwise, the available scan elements in the two plan groups are assigned to the scan chain And placing the scan chain into the third scan chain set. The method for reconstructing a scan chain according to claim 1, wherein the step 4 further comprises: extracting a scan chain of the scan element from the third scan chain set; checking whether there is a scan available in the plan group. The number of components is more than the number of scanning components required for a scan chain that requires the most; if so, the scan chain is selected from a plan group containing the fewest number of scan components; otherwise, the number of scan components having the largest number of available scan components is included. The group begins to assign scanning elements to the scan chain and finally selects the scanning elements to the top layer. The method of reconstructing a scan chain according to any one of claims 1-6, further comprising a second stage reconstruction in which the scan elements required for the scan chain within the same plan group are reconstructed The location will be redistributed based on the scan component. The method of reconstructing a scan chain according to claim 7, wherein scanning elements adjacent to and adjacent to a scan chain are to be allocated to the scan chain. A scan chain reconstruction apparatus includes a first level reconstructor, the first stage reconstructor comprising: a classifier for classifying a plurality of scan chains, wherein the start point and the end point are within a same plan group The scan chain is classified into the first scan chain set, and the scan chain whose start point and end point are not in the same plan group is classified into the second scan chain set, and the start and end points are classified into the third scan chain set in a top scan chain; a distributor, in communication with the classifier, first reconstructing the scan chain for each scan chain in the first scan chain set by using scan elements in the same plan group corresponding to the scan chain until the A scan chain set is empty, wherein if the required scan elements of the reconstructed scan chain cannot be satisfied by the remaining scan elements in the corresponding plan group, the corresponding plan group is The remaining scanning elements are given to the scan chain and the scan chain is moved into the third scan chain set, and then for each scan chain in the second scan chain set, different scan plan groups corresponding to the scan chain are utilized. Inner sweep Reconfiguring the scan chain until the second scan chain set is empty, wherein if the desired scan element of the reconstructed scan chain cannot be satisfied by the remaining scan elements in its corresponding different plan group, then Will The remaining scan elements in the corresponding different plan groups are given to the scan chain and the scan chain is moved into the third scan chain set, and finally the scan chain in the third scan chain set is reconstructed until the third The scan chain set is empty. The apparatus for reconstructing a scan chain according to claim 9, wherein the identifier extracts a scan from the first scan chain set that requires the least number of scan components when reconstructing the scan chain in the first scan chain set Chaining, and checking whether the number of available scanning elements in a plan group of the end of the scan chain satisfies the scan chain requirement; if sufficient, assigning available scan elements in the plan group according to the required number of scan chains The scan chain, otherwise all of the available scan elements in the plan set are assigned to the scan chain and placed in the third scan chain set. The apparatus for reconstructing a scan chain according to claim 9, wherein the allergen requires a minimum number of scans to be taken from the second scan chain set when reconstructing the scan chain in the second scan chain set a chain, determining whether the number of available scanning elements in the planning group of the scanning end point satisfies whether the scanning chain has an end point at the top layer; if so, determining another scanning chain of the scanning chain, otherwise, for the scanning chain The two plan groups in which the two endpoints are located, respectively, calculate the total number of scan component requirements for all scan chains from which the scan elements may be selected. The apparatus for reconstructing a scan chain according to claim 11, wherein the allocator determines whether the number of available scan elements in the plan group of the other end of the scan chain satisfies the scan chain requirement; Number of scanning elements If sufficient, the scanning elements in the planning group are allocated to the scanning chain according to the required number, otherwise the scanning elements in the planning group are assigned to the scanning chain, and the scanning chain is added to the third scanning chain set. The apparatus for reconstructing a scan chain according to claim 11, wherein the allocator determines whether the available scan elements in the two plan groups meet the needs of the scan chain when the scan chain has no endpoints at the top layer; If yes, the scan component is preferentially assigned to the scan chain from a plan group having a smaller total number of corresponding scan component requirements, and the insufficient amount is selected from another plan group, otherwise the available scans in the two plan groups are The components are assigned to the scan chain and the scan chain is placed in a third scan chain set. The apparatus for reconstructing a scan chain according to claim 9, wherein the allergen extracts a scan of the desired scan component from the third scan chain set while reconstructing the scan chain in the third scan chain set Chain; check if a plan group contains more scan elements than the most demanding scan chain; if so, the scan chain is selected from a plan group with the fewest scan elements, otherwise A scan element is assigned to the scan chain starting from a plan group containing the largest number of available scan elements, and finally to the top level selection. The apparatus for reconstructing a scan chain according to claim 14, further comprising a second level reconstructor communicatively coupled to the first level reconstructor, the scan chain reconstructed by the first level reconstructor The scan elements required for the scan chain within the same plan group are redistributed based on the scan element position. A reconstruction apparatus for a scan chain according to claim 15, wherein the second reconstructor distributes a scanning element adjacent to and away from a scan chain to the scan chain.